Evaluation of the Ameliorative roles of Vitamins A, C and E on Aspartate Amino Transferase (AST) production in Clarias gariepinus (Burchell, 1822) Fingerlings exposed to Cadmium Chloride

Abstract

The anthropogenic activities culminating in environmental pollution usually lead to release of plethora of pollutants such as cadmium calls for concern. The effects of CdCl2 on the production of aspartate amino transferase (AST) in C. gariepinus and how they can be ameliorated through administration of vitamins were investigated. C. gariepinus fingerlings (whose initial weight ranged from 3-11g) were exposed to sub-lethal concentrations of Cd (00, 12mg/L, 16mg/L, 20mg/L and 24mg/L) with replicate in each case. In each case, 12mg/L of the vitamin was administered across all buds. Fresh concentrations of both toxicant and vitamins were administered every 72 hours for a period of 12 weeks every time the water medium was changed. The various treatments group include Cd only, CdVA, CdVC and CdVE. 3 samples of the fish were randomly selected and sacrificed from each aquarium tank every 2 weeks of the exposure period. The gills, kidneys and liver were excised from these specimens and homogenized in sodium phosphate buffer. From the results: in Cd only, the highest AST produced in the liver was 135.00±0.18nM/mg in T1. The highest AST produced in the kidneys of the fish was 145.00±0.18nM/mg in T3. The highest AST produced in the gill was 137.97±0.09nM/mg in T1. In CDVA samples, the highest AST produced in the liver was 132.19±0.18nM/mg in T4. The highest AST produced in the kidneys was 113.91±0.09nM/mg in T1. In the gills, the highest AST value was 120.94±0.36nM/mg in T1. In the samples exposed to CdVC, the highest AST produced in the liver was 128.44±0.36nM/mg in T1. The highest mean value of AST produced in the kidneys was 114.84±0.09nM/mg in T3. In the gills of the samples, the highest AST value was 125.16±0.27nM/mg in T2. In CdVE samples, the highest AST produced in the liver was 150.63±0.18nM/mg in T2. The kidneys’ highest AST value of 125.78±0.27nM/mg was recorded in T4. In the gills of the samples, the highest AST produced in the gills of the fish was 133.28±0.09nM/mg in T1. There were general high production levels of AST in all treatments with the highest values recorded in the liver of CdVA, CdVC and CdVE groups mostly in samples exposed to lower concentrations. The kidneys in the Cd only group however, produced the highest AST value. The high production values of AST in all treatments suggest that the enzyme is a good biomarker of oxidative stress elicited by the presence of the toxicant.